WO2015043233A1

WO2015043233A1 - Base station device for supporting data transmission based on high-order modulation, and data communication method

Info

Publication number: WO2015043233A1
Application number: PCT/CN2014/079485
Authority: WO
Inventors: 郑萌; 耿璐; 水谷美香
Original assignee: 株式会社日立制作所; 郑萌; 耿璐; 水谷美香
Priority date: 2013-09-25
Filing date: 2014-06-09
Publication date: 2015-04-02
Also published as: CN104468027A

Abstract

A base station device and a data communication method. The base station device comprises: a receiving unit which receives channel state information containing a CQI index from a terminal device; a high-level link unit which generates a high-level signalling sending signal and sends same to the terminal device, and designates whether the terminal device uses a basic CQI mapping table or an extended CQI mapping table in the high-level signalling sending signal, the extended CQI mapping table specifying the correlation between the CQI index and an extended modulation manner and a code rate, and the extended modulation manner comprising a high-order modulation manner with a higher order of modulation; an information collection unit which maps the CQI index into information about the signal to interference plus noise ratio according to the designated CQI mapping table; a scheduling unit which conducts channel resource allocation on the terminal device according to the mapped information about the signal to interference plus noise ratio and selects a modulation and coding scheme; and a sending unit which generates a downlink transmission signal according to a scheduling result and sends same to the terminal device.

Description

Base station apparatus and data communication method supporting data transmission based on high-order modulation

The present invention relates to a method, a base station apparatus and a terminal apparatus for transmitting data to a terminal by a base station as a wireless communication device. More particularly, it relates to a base station apparatus and a data communication method capable of supporting high-order modulation based data transmission by performing downlink data transmission using a flexible downlink coding scheme. Background technique

Link adaptation technology means that the information sender obtains the current channel quality information of the channel in some way, and selects a suitable modulation and coding scheme (MCS) for the receiver based on the information, and performs channel for the transmitted information. The process of encoding, modulating, and transmitting to take advantage of channel capacity to achieve higher data rates. In a wireless network, a base station and a terminal (UE) pre-arrange the coding mode, a code rate, and a modulation mode that may be used by the system. When actually performing data transmission, determine the MCS based on the specific information contained in the signaling and select an appropriate coding. A decoder and modem that transmit and receive data signals. If the indication information is incorrect or the sender uses a modulation and coding scheme that is not supported by the receiver, the reception of the information will fail.

In the Long Term Evolution (LTE) standard developed by the 3GPP organization, when the system performs downlink data transmission, the base station can select a convolutional code or a turbo code, and implement various possible code rates by using rate matching technology. A channel-coded bit stream is generated; then the base station can select QPSK, 16QAM or 64QAM to modulate the code bit stream, generate a specific modulation symbol, and then process the signal through the antenna through subsequent multi-antenna processing. The terminal selects a corresponding demodulation and decoder according to the downlink physical layer control signaling information sent by the base station, and attempts to receive the data.

The information carrying capacity of different modulation methods is different. A QPSK symbol can only carry 2 bits, and a 64QAM symbol can carry 6 bits. Since the same modulation symbol occupies the same resource element (Resource Element, RE) on the resource grid, it is in the same Under the premise of the code rate, the data transmission rate of the latter is three times that of the former. At the same time, the latter is much more sensitive to interference and noise than the former, which means that when interference or noise is strong, the reception of 64QAM modulation symbols will cause a large number of errors, and thus offset the higher symbol carrying rate. The benefits. Therefore, using 64QAM for data transmission can only bring benefits at a higher signal-to-noise ratio, that is, a higher channel capacity. The 3GPP reports the quantized channel quality information called Channel Quality Indicator (CQI) to the base station by means of feedback. Based on this information, the base station determines the MCS used for data transmission. When the channel quality is good enough, the LTE base station can transmit using 64QAM modulated symbols. The modulation method, together with the highest code rate that the Turbo code rate matching supported by the LTE system can reach, determines the upper limit of the downlink transmission rate of the LTE system. In a typical macro cell coverage scenario, the reachable signal to interference and noise ratio of the LTE system is limited. Therefore, in the prior art, the MCS based on the modulation mode up to 64QAM can fully utilize the channel capacity.

High-order modulation is of course not limited to 64QAM. For example, there is also 256QAM. When the number of constellation points in the modulation mode is increased from 64 to 256, the number of bits carried by a 256QAM symbol is from 8 to 8, so that the data transmission rate is increased by 33. %. However, since 256QAM is more sensitive to interference and is suitable for a higher signal-to-noise ratio environment, 256QAM has almost theoretical application possibilities in the current cellular network environment where 64QAM cannot be reliably covered.

On the other hand, as an effort to improve the wireless network environment, research on microcell enhancement has been introduced in LTE Rel. The so-called micro cell refers to a cell whose signal transmission power is much smaller than that of a macro cell, and is usually used for a base station device with small coverage or hot spot enhancement. The micro cell may be placed in an area where the macro cell coverage is unreachable as shown in FIG. 1(a), or a frequency band independent of the macro cell is as shown in FIG. 1(b). In scenario (a) in the example, the signal from the 101 macro base station 1 cannot reach 103 terminal 1 (the signal strength is much smaller than the noise) due to the large fading and the blockage of the building walls. At the same time, the 102 micro base station 1 covers the interior of the building using the same carrier frequency 104 as the macro base station 1. At this time, the terminal 1 is close to the micro base station 1, and is not subject to the same-frequency interference from the neighboring cell, and can obtain a signal-to-noise ratio better than that in the conventional macrocell scenario. In the scenario illustrated in Figure 1 (b), 101 macro base stations 1 and 102 micro base stations 2 operate on different carrier frequencies 104 (fl ) and 105 (: £ 2:). The 103 terminal 1 located in the micro zone can access the carrier frequency of the micro base station 2 while the signal from the macro base station 1 is filtered out. The terminal 1 can also receive signals of the same carrier frequency of other micro base stations, such as the micro base station 1, but if the distance is far, the attenuation is more serious than the useful signal of the serving cell. Then, the terminal 1 can also obtain a signal to interference and noise ratio better than that in the traditional macro cell scenario. A higher signal to interference and noise ratio means a higher reachable channel capacity. At this time, the existing MCS in the LTE system only to 64QAM may limit the utilization of the channel capacity, so the introduction of a more efficient modulation method such as 256QAM or even higher order can effectively improve the transmission efficiency of the terminal 1, thereby Brings an overall improvement in system performance.

At the same time, LTE has introduced various interference suppression techniques in existing versions, such as enhanced small-area interference cancellation or multi-point cooperation. These techniques can generally reduce interference from neighboring cells and even enhance the strength of useful signals, thereby achieving better signal to interference and noise ratio than in traditional macro cell scenarios. Therefore, the introduction of a more efficient modulation scheme such as 256QAM may also improve the transmission efficiency of the target terminal that benefits from the existing interference suppression technology, resulting in an overall improvement in system performance.

In order to introduce a new modulation scheme, a new MCS combination needs to be defined. These new combinations need to be simultaneously supported by the base station and the terminal and recorded in the MCS information table. At the same time, in order to ensure backward compatibility, the original MCS form still needs to be retained in the system. In this way, in the new system, multiple sets of MCS tables need to be defined, and related feedback and scheduling processes are defined to support.

In Patent Document 1 (US2009010211A1), a base station-terminal system that can support multiple sets of MCS tables is defined. In each different set of MCS tables, the same MCS scheme corresponds to different thresholds. The technical problem addressed by Patent Document 1 is that there is usually an error in the CQI reporting of the terminal in an actual system. In order to compensate for this error as much as possible, the base station of Patent Document 1 classifies all terminals into different levels, and then uses different MCS tables for different levels of UEs. For example, the CQI reported by the terminal of Level 1 is greater than its actual SINR value. If the MCS table corresponding to the exact threshold is used for mapping, it will result in a higher error rate. Therefore, the base station selects an MCS table in which there is a positive offset between the mapping threshold of each MCS and its precise threshold, i.e., only a relatively higher signal to interference and noise ratio value in the table can be mapped to the MCS. By configuring different mapping thresholds for the same MCS in different tables, the base station can classify the terminals and use different MCS tables to obtain more accurate mapping results and compensate the CQI estimation errors of the terminals to improve system performance.

However, the method of selecting a suitable MCS table for different terminals by the base station of Patent Document 1 is not intended to further achieve a higher transmission rate by using the channel capacity, but to deal with the adverse effects caused by the channel estimation deviation of the UE. A combination of identical modulation coding schemes is used between different MCS tables, the only difference being the range of the signal to interference and noise ratio of the mapping. Base station can This method is used to effectively track changes in channel quality, but cannot support extended MCS schemes.

In Patent Document 2 (WO2012119549A1), a new relationship between a MCS table supporting 256QAM and a Downlink Block Size (TBS) is described and various embodiments are given. On this basis, how to extend the MCS-TBS mapping from single-layer transmission to the MCS-TBS mapping relationship in multi-layer transmission is given. However, this document only gives the MCS table supporting 256QAM, but does not give the specific structure and method to support the new MCS table in the LTE system. Summary of the invention

The present invention has been made in view of the above problems, and an object thereof is to provide a two-layer CQI mapping table by setting a basic CQI mapping table including an existing modulation scheme and an extended CQI mapping table including a high-order modulation scheme such as 256QAM. Select between them to improve CSI feedback accuracy, assist in dynamically determining the MCS scheme for downlink transmission, to make full use of channel capacity by implementing higher-order modulation methods such as 256QAM, and to maintain the relationship with existing mechanisms. A well-compatible base station apparatus and a communication method in a wireless communication system.

According to an aspect of the present invention, a base station apparatus is provided, which determines a modulation and coding scheme and transmits and receives a data signal by using a feedback information generated based on a CQI table with a terminal apparatus in a wireless communication system, and is characterized by including Receiving, receiving, from the terminal device, channel state information including a CQI index indicating channel quality; a higher layer link unit, generating a high layer signaling signal and transmitting to the terminal device, the high layer link unit according to the receiving unit Received channel state information, in which the CQI table used by the terminal device is specified in a basic CQI mapping table or an extended CQI mapping table, wherein the basic CQI mapping table specifies the CQI Corresponding relationship between the index and the modulation mode and the code rate, the extended CQI mapping table specifies a correspondence between the CQI index and the extended modulation mode and the code rate, and the extended modulation mode includes the basic CQI mapping table Modulation mode and modulation order are higher than the basic CQI mapping table a high-order modulation mode of the modulation mode; the information collecting unit, mapping the CQI index into the signal to interference and noise ratio information according to the basic CQI mapping table or the extended CQI mapping table specified by the higher layer link unit for the terminal device; According to the signal to interference and noise ratio information mapped by the information collecting unit, the terminal device is And performing, by the transmitting unit, generating a downlink transmission signal and transmitting the signal to the terminal device according to the resource allocation result of the scheduling unit and the modulation and coding scheme selection result.

Therefore, the present invention improves the CSI feedback accuracy by setting a basic CQI mapping table including an existing modulation scheme and an extended CQI mapping table including a high-order modulation scheme such as 256QAM to select a CQI mapping table. It assists in dynamically determining the MCS scheme for downlink transmission, and fully utilizes the channel capacity by implementing higher-order modulation methods such as 256QAM, while maintaining good compatibility with existing mechanisms.

In addition, in the above-mentioned base station apparatus, the terminal apparatus may be configured with at least one CSI feedback object, where the CSI feedback object is a different channel state information reference signal CSI-RS resource and channel state of the terminal apparatus in a network environment. Information interference measurement CSI-IM resource combination; the high-level link unit specifies, for each CSI feedback object of the terminal device, whether the used CQI table is a basic CQI mapping table or an extended CQI mapping table; the information collecting unit Mapping the CQI index to the signal to interference and noise ratio information for each CSI feedback object of the terminal device; the scheduling unit determines a corresponding CSI feedback object based on the signal source and interference status of the terminal device, according to the information collecting unit The signal to interference and noise ratio information mapped by the corresponding CSI feedback object of the terminal device performs channel resource allocation on the terminal device and selects a modulation and coding scheme.

The present invention not only targets the terminal, but also specifies a basic CQI mapping table or an extended CQI mapping table for the CSI feedback object of the terminal, and the CSI feedback object corresponds to different channel state/interference scenarios of the terminal in the actual network environment, thereby being able to The specific CSI feedback object of the designated terminal uses a specific CQI mapping table to achieve a more accurate MCS scheme configuration for the terminal in the actual network environment.

In addition, in the base station apparatus, when the CSI feedback object of the terminal apparatus is currently using the basic CQI mapping table, the higher layer link unit determines whether the CQI value based on the current downlink transport block scheduling is equal to the basic The maximum value of the CQI in the CQI mapping table, and whether the transmission rate of the MCS used in the transmission of the downlink transport block is greater than or equal to the transmission rate corresponding to the maximum CQI of the basic CQI mapping table. If the results of both determinations are yes, Then, an extended CQI mapping table is specified for the CSI feedback object of the terminal device.

If the CQI value based on the current downlink transport block scheduling has not reached the maximum CQI value in the basic CQI mapping table, it indicates that the SINR value of the current channel of the terminal does not exceed the basic CQI mapping. The mapping range of the table does not need to be switched to the extended CQI mapping table of the higher modulation mode; likewise, if the transmission rate of the MCS used in the downlink transport block transmission is smaller than the transmission rate corresponding to the maximum CQI of the basic CQI mapping table, It is indicated that the transmission of the downlink transport block is not sufficient as a basis for performing the CQI mapping table switching judgment, and the basic CQ mapping table can be continued at this time. Only when the results of both judgments are yes, switch to the extended CQI mapping table based on the higher modulation mode. In this way, the present invention can make full use of the existing basic mapping table, and switch when there is a need to switch to the extended mapping table in a suitable network environment, thereby reducing unnecessary switching and maintaining the quantization precision of the CSI feedback. To make full use of channel capacity reasonably.

In addition, in the foregoing base station apparatus, each of the CQI indexes respectively corresponds to a mapping threshold, where the mapping threshold is a value reflecting a one-to-one mapping rule between a CQI and an SINR value; If the result of the determination is yes, the higher layer link unit further calculates whether the ACK/NACK information received by the receiving unit is a NACK or an ACK pair cumulative offset value S. _{The ffset} is updated, and it is determined whether the mapping threshold T _hlgh corresponding to the CQI with the highest transmission rate of the high-order modulation and the lowest transmission rate in the extended CQI mapping table is smaller than the mapping threshold T _w corresponding to the maximum CQI in the basic CQI mapping table. And the sum of the updated cumulative offset value S _ffset , if Thigj^T ^+Sc^et, the extended CQI mapping table, the accumulated offset value S, is specified for the CSI feedback object of the terminal device. The initial value of _ffset is 0 dB, and if the ACK/NACK information is ACK, the accumulated offset value S. _Ffset is updated to S _ffset = Soffeet + Step _up , where Step _up is the transition offset when the received information is successfully transmitted, and if the ACK/NACK information is NACK, the accumulated offset value S. _Ffset is updated to S _ffset = S _offS et - Step _d where Step _down is the aggressive offset when the information is not successfully transmitted, Step _up and Stepd are fixed values in the range of 0.04dB~0.2dB and 0.4dB~ldB respectively. .

Thus, the present invention sets the cumulative value S based on continuous updating. _{Whether the ffset} triggers the reconfiguration process can avoid the "ping-pong effect" that the transient judgment mechanism may bring, avoiding waste of resources, and realizing reconfiguration between CQI mapping tables more suitable for practical applications.

In addition, in the above-mentioned base station apparatus, the high-layer link unit may determine whether the current downlink transport block is the initial transmission before performing the two determinations, and when the initial transmission is performed, perform the two Judge.

If the current downlink transport block is a retransmission block, it cannot be used as the SINR value of the current channel. The basis of the mapping range of the current CQI mapping table is exceeded. Therefore, if it is determined that the initial transmission is performed, the determination of whether or not to trigger the reconfiguration is performed, and a system closer to the actual application requirement can be realized.

In addition, in the foregoing base station apparatus, each of the CQI indexes respectively corresponds to a mapping threshold, which is a value reflecting a one-to-one mapping rule between a CQI and an SINR value; CSI in the terminal device When the feedback object is currently using the extended CQI mapping table, the high-layer link unit determines whether the CQI value based on the current downlink transport block scheduling is greater than or equal to the CQI minimum value of the high-order modulation mode used in the extended CQI mapping table, according to the judgment. The result is a cumulative offset value of K. _{The ffset} is updated, and the mapping threshold T3⁄4 corresponding to the maximum CQI value in the basic CQI mapping table is determined. Whether _w is larger than the mapping threshold TH _hlgh corresponding to the CQI with the highest transmission rate of the high-order modulation and the accumulated cumulative offset k in the extended CQI mapping table. _{The sum} of _ffset , if TH _low >TH _hlgh +k _offset , specifies a basic CQI mapping table for the CSI feedback object of the terminal device, the accumulated offset value. _The initial value is 0 dB, and if it is determined that the CQI value based on the current downlink transport block scheduling is greater than or equal to the CQI minimum value of the high-order modulation scheme used in the extended CQI mapping table, the accumulated offset value! ^ was updated to! ^ :! ^ +! ^, where R _up is an edge offset value when receiving a CQI using high-order modulation, and multiplying a difference value of a minimum CQI using a high-order modulation method in the reported CQI and the extended CQI mapping table by a first predetermined value The product determines, if it is determined that the CQI value based on the current downlink transport block scheduling is smaller than the CQI minimum value of the high-order modulation scheme used in the extended CQI mapping table, the accumulated offset value K. _Ffset is updated to K. _Ffset = K _offset - R _down , where R _d . Wn is an edge offset value when receiving a CQI that is not using high-order modulation, and is determined by multiplying a difference between a minimum CQI and a reported CQI of a high-order modulation method in the extended CQI mapping table by a second predetermined value. The first predetermined value and the second predetermined value are arbitrary values greater than 0 and less than 1, and the second predetermined value is smaller than the first predetermined value.

Thus, the present invention provides a reconfiguration mechanism for switching from an extended CQI mapping table to a basic CQI mapping table, and a cumulative value K based on constant updating is also set in the reconfiguration mechanism. _Ffset determines whether to trigger the reconfiguration process, so it can avoid the "ping-pong effect" that the transient judgment mechanism may bring, avoid waste of resources, and realize reconfiguration between CQI mapping tables more suitable for practical applications.

In addition, in the base station apparatus, the basic CQI mapping table may be The number of CQI indexes is the same as the number of CQI indexes in the extended CQI index table.

The equal number of CQI indexes between the new extended CQI mapping table and the existing basic CQI mapping table can keep the size of the tables consistent, which saves many other aspects of redesign and maintains good backward compatibility.

Furthermore, in the above-described base station apparatus, the modulation scheme in the basic CQI mapping table may include QPSK, 16QAM, and 64QAM, and the high-order modulation scheme is a modulation scheme in which the modulation order is 256QAM or more.

The present invention also provides a data communication method in a wireless communication system corresponding to the above-described base station apparatus, wherein the base station apparatus and the terminal apparatus determine the modulation and coding scheme by using the feedback information generated based on the CQI table, and transmit and receive the data signal. The data communication method includes the following steps: receiving, the base station apparatus receiving, by the terminal apparatus, channel state information including a CQI index indicating a channel quality; a high-layer link step, the base station apparatus Generating a high-level signaling signal and transmitting it to the terminal device, where the base station device further determines, according to the channel state information received by the receiving step, a CQI table used by the terminal device in the high-layer signaling signal The CQI mapping table is also specified by an extended CQI mapping table, wherein the basic CQI mapping table specifies a correspondence between the CQI index and a modulation mode and a code rate, and the extended CQI mapping table specifies the CQI index and extension. The relationship between the modulation mode and the code rate, the extended tone The method includes: a modulation mode in the basic CQI mapping table and a high-order modulation mode in which a modulation order is higher than a modulation mode in the basic CQI mapping table; and an information collecting step, the base station device is configured according to the high-layer link The basic CQI mapping table or the extended CQI mapping table for the terminal device specified in the step is to map the CQI index to the signal to interference and noise ratio information; and the scheduling step, the base station device according to the information collected by the information collecting step The noise ratio information, the channel resource allocation is performed on the terminal device, and the modulation and coding scheme is selected; and the transmitting step, the base station device generates a downlink transmission signal according to the resource allocation result of the scheduling step and the modulation and coding scheme selection result, and generates a downlink transmission signal The terminal device transmits.

Therefore, according to the present invention, by transmitting information for configuring a CQI mapping table on which a specific CSI feedback object is based on a high-layer link, the network can flexibly perform an MCS table for downlink data transmission according to an interference condition of a specific terminal and a real-time transmission mode. The choice makes it possible to introduce new and efficient modulation methods.

Since the present invention enhances the accuracy of feedback and scheduling, the transmission rate in the network is improved. The limit is beneficial to fully exploit the channel capacity in a specific scenario. Therefore, the performance of the network can be effectively improved. DRAWINGS

1 is a schematic diagram showing a typical scenario including a micro cell and a macro cell in the present invention. Fig. 2 is a diagram showing an example of a basic CQI mapping table including only a low-order modulation technique in the present invention.

Fig. 3 is a view showing an example of a scenario of a plurality of CSI feedback objects arranged for a terminal in the present invention. Fig. 4 is a view showing an example of an extended CQI mapping table including a new high-order modulation method in the present invention.

Fig. 5 is a block diagram showing the internal base station of the present invention which supports the introduction of a high-order modulation scheme.

Fig. 6 is a view showing an example of a base station side RRM measurement result storage table in the present invention.

Fig. 7 is a view showing an example of a base station side SINR information storage table in the present invention.

Fig. 8 is a diagram showing an example of a base station side HARQ information storage table in the present invention.

Fig. 9 is a view showing an example of CSI feedback related configuration information of the base station side high layer configuration information storage table in the present invention.

Figure 10 is a flow chart showing the switching from the basic CQI mapping table not including high-order modulation to the extended CQI mapping table including high-order modulation in the present invention.

Figure 11 is a flow chart showing the switching from the extended CQI mapping table including the high-order modulation to the basic CQI mapping table not including the high-order modulation in the present invention.

Fig. 12 is a diagram showing an example of a base station side CQI history information storage table in the present invention.

Figure 13 is a diagram showing an example of a sequence of complete base station-terminal downlink data transmission in the present invention. Figure 14 is a diagram showing an example of the format of signaling information transmitted on a higher layer link involved in the present invention.

Fig. 15 is a view showing an example of the flow of downlink data transmission in the present invention.

Fig. 16 is a view showing an example of MCS-TBS index mapping in the present invention.

Fig. 17 is a diagram showing an example of TBS index-TBS mapping in the present invention.

Figure 18 is a diagram showing an example of a format for instructing a terminal to receive downlink control information for receiving a downlink transport block using high-order modulation in the present invention.

FIG. 19 is a diagram showing downlink data supported by using MCS based on high-order modulation in the present invention. Internal block diagram of the transmitted terminal.

Fig. 20 is a view showing an example of CSI feedback related configuration information of the terminal side high layer configuration information storage table in the present invention.

Fig. 21 is a view showing an example of the flow of the CSI measurement and feedback method on the terminal side in the present invention. Fig. 22 is a view showing an example of the flow of downlink data reception in the present invention.

FIG. 23 is a diagram showing an example of a resource grid of a downlink transmission in an existing system. detailed description

The cell concept in the present invention may be a coverage range of a base station, a sector of a base station, a home base station (micro base station), or a transmission point (TP). To simplify the description, the cell is represented by a range covered by a base station (micro base station).

The CSI feedback object concept in the present invention refers to a combination of different CSI Reference Signal (CSI-RS) resources and CSI Interference Measurement (CSI-IM) resources of the terminal in a network environment. . Each terminal may be configured with multiple CSI feedback objects according to different CSI-RS and CSI-IM combinations, and may be used for each CSI feedback object, according to the signal strength measured based on its linked CSI-RS, and based on CSI- The interference strength measured by the IM, the CSI feedback information is calculated and reported independently, and the specific details about the CSI feedback object will be described in detail later with reference to FIG. 3 and FIG. 23.

The CQI concept in the present invention refers to an indication that the terminal calculates and reports a specific CSI feedback object indicating the current channel quality. The terminal maps the calculated SINR value to CQI according to a predetermined method according to a previously agreed CQI mapping table. Fig. 2 is a view showing an example of a CQI mapping table (basic CQI mapping table) including only a low-order modulation method in the present invention. This table is a mapping table of CQIs used in the current LTE system, and specifies a modulation scheme 202 and an encoding code rate 203 corresponding to each CQI index (CQI index, taking values from 0 to 15) 201. The table also shows the transmission efficiency 204 for this modulation scheme in combination with the code rate. The basic CQI mapping table mentioned in the present invention includes but is not limited to the correspondence between the CQI index and the modulation mode and the code rate given in this example table, and the CQI mapping table (basic CQI mapping table of the present invention containing only the low-order modulation mode) As long as the correspondence between the CQI and the modulation mode and the code rate is specified, the modulation mode may be, for example, a modulation mode in which the modulation order is 64QAM or less, including but not limited to QPSK, 16QAM, and 64QAM. The CQI mapping process of the terminal on a specific CSI feedback object is Based on the calculated SINR, a combination of the modulation scheme recommended to the base station and the code rate is generated according to a certain method. The method for generating the above mapping may be a method in the LTE system, or may be other implementable methods, which are well known to those skilled in the art and are not directly related to the present invention. Narration.

Fig. 3 is a view showing an example of a scenario of a plurality of CSI feedback objects arranged for a terminal in the present invention. As shown in Figure 3, the two micro base stations 102 form two adjacent cells, respectively. Each terminal has an active terminal 103 in which each terminal 1 is located in a cell formed by the micro base station 1, and the terminal 2 is located in a cell formed by the micro base station 2. The terminal 1 accesses the micro base station 1, but at the same time, because it is located at the junction of the two cells, the useful signal 301 from the micro base station 1 and the interference signal 302 from the micro base station 2 are simultaneously received. In order to improve the channel quality of the terminal 1, different scenarios can be considered. For example, the micro base station 2 can be silenced on a part of the subframes, thereby eliminating interference to the terminal 1 on these subframes. The channel quality of the terminal 1 is not limited to this scenario, and other scenarios may be considered. In order to obtain accurate CSI information for different scenarios in the scenario of FIG. 3, the concept of CSI feedback objects is entered, and different CSI feedback object links are used. The combination of CSI-RS resources and CSI-IM resources in different scenarios, and the combination of different CSI-RS resources and CSI-IM resources are respectively used to reflect the channel conditions of the useful signals in different scenarios under consideration and The interference situation, using Fig. 23, further illustrates the concept of an accurate CSI feedback object corresponding to the different scenarios of Fig. 3.

Figure 23 is an example of a resource grid for downlink transmission in an existing system. The cell reference signal 2301 is a cell-specific reference signal for physical layer measurements and channel measurements in certain transmission modes.

The PDCCH resource element 2302 is configured to transmit a PDCCH signal and carry downlink control information. The PDSCH resource element 2303 is used to transmit a PDSCH signal and carry downlink data. To enhance CSI feedback accuracy, the network can configure multiple CSI-RS resources and CSI-IM resources for the same terminal. Taking the terminal 1 in FIG. 3 as an example, the stronger signals received by the terminal 1 are from the micro base station 1 and the micro base station 2, so the network configures two CSI-RS resources for it, where the CSI-RS resource 1 (2304) is configured by The micro base station 1 transmits, the terminal 1 can measure the channel state parameter of the micro base station 1 - terminal 1 through the resource; the CSI-RS resource 2 (2305) is sent by the micro base station 2, and the terminal 1 can measure the micro base station 2 - the terminal 1 through the resource Channel state parameters. At the same time, the network is configured with two CSI-IM resources, wherein the CSI-IM resource 1 (2306) has a signal transmitted by the micro base station 2, and the terminal 1 can measure the interference caused by the operation of the micro base station 2 through the resource; -IM resource 2 (2307) does not exist on the micro base station 2 The transmitted signal, through which the terminal 1 can measure the interference caused by the micro base station 2 when it is silent. In the example of configuring a plurality of feedback objects for the terminal 1 shown in FIG. 3, the combination of the CSI-RS resource 1 and the CSI-IM resource 1 to which the CSI feedback object 1 is linked may be the CSI reported by the CSI feedback object 1. For the case where the interference signal of the signal from the micro base station 1 and the micro base station 2 exists; the combination of the CSI-RS resource 1 and the CSI-IM resource 2 to which the CSI feedback object 2 is linked, then the CSI reported by the CSI feedback object 2 is directed to the signal The case where the interference signal from the micro base station 1 and the micro base station 2 does not exist; the combination of the CSI-RS resource 2 and the CSI-IM resource 2 to which the CSI feedback object 3 is linked, the CSI reported by the CSI feedback object 3 is directed to the signal from the micro The case where the interference signal of the base station 2 and the micro base station 1 does not exist. At this time, the CSI feedback objects 1 to 3 correspond to the above three different scenarios as described above, wherein the SINR value and the corresponding channel capacity value of the downlink channel when the micro base station 2 is silent may be higher than that calculated by the CSI feedback object 2 The upper limit of the reach of the CSI feedback object 1 and even the legacy LTE network is such that there is a possibility that the high-order modulation mode of 256QAM or more can be used to increase the reachable transmission rate of the terminal 1 when the micro base station 2 is dynamically muted. At this time, the CSI feedback object 2 can use the CQI mapping table of the present invention including a new high-order modulation method. Similarly, for the CSI feedback object 3, although the signal from the micro base station 2 is weaker than the signal from the micro base station 1, since there is no strong interference, the CQI mapping of the present invention including the new high order modulation method can also be used. form.

4 is a diagram showing an example of a CQI mapping table (extended CQI mapping table) including a new high-order modulation method of the present invention. The same portions as those of the CQI mapping table of Fig. 2 are denoted by the same reference numerals. The table of Fig. 4 also specifies the modulation scheme 202 corresponding to each CQI index 201. The table also gives the coding rate 203 corresponding to each CQI index and the transmission efficiency 204 in combination with the modulation scheme and the code rate. This table is characterized in that the existing CQI mapping table of FIG. 2 is characterized by adding a combination based on a higher order modulation scheme such as 256QAM and different code rates and specifying a corresponding CQI mdex. The extended CQI mapping table of the present invention including the new high-order modulation mode includes, but is not limited to, the correspondence between the CQI index and the modulation mode and the code rate given in this example table; in addition, the CQI mdex of the table of FIG. The number is the same as the number of CQI indexes in the table in Figure 2, both of which are 0~15. The number of CQI indexes between the new extended CQI mapping table and the existing basic CQI mapping table can be kept the same size between the tables. Save a lot of other aspects of redesigning. The CQI mapping table (extended CQI mapping table) including the new high-order modulation method of the present invention only specifies the CQI and the extended modulation method. And the correspondence between the code rates, wherein the so-called spread modulation method includes a modulation method in the basic CQI mapping table and a high-order modulation method in which the modulation order is higher than the modulation mode in the basic CQI mapping table, and preferably, The number of CQI indexes between the new extended CQI mapping table and the existing basic CQI mapping table is equal, and the high-order modulation method here may be, for example, a modulation mode in which the modulation order is above 256QAM. The CQI mapping process of the terminal on the specific CSI feedback object is based on the calculated SINR, and a combination of the modulation mode recommended by the base station and the coding code rate is generated according to a certain method. Similarly, the method for generating the above mapping may be a method in the LTE system, or may be other achievable methods, which are well known to those skilled in the art and are not directly related to the present invention. No longer.

FIG. 5 is an internal block diagram of a base station supporting the introduction of a high-order modulation scheme in the present invention.

As shown in FIG. 5, the base station that supports the introduction of the high-order modulation mode mainly includes: a high-layer signaling configuration unit 517, a high-layer information processing unit 520, a physical layer receiving unit 501, a physical layer sending unit 516, an information collecting unit 502, and a CQI mapping table. The decision unit 528, the storage unit 523, the scheduling unit 507, the PDCCH generating unit 510, and the PDSCH generating unit 512.

Specifically, the higher layer signaling configuration unit 517 and the higher layer information processing unit 520 are modules related to higher layer link behavior. The high-level link refers to a virtual logical communication link established between high-level functional entities located above the physical layer according to a layered model in a communication system. The high-level functional entity is configured to process information transmitted on a high-level link and complete a communication function defined at a higher layer. A typical example of the high layer described in the present invention is a Radio Resource Control layer (RRC layer) in an LTE system. The high-layer signaling configuration unit 517 and the high-level information processing unit 520 are configured to establish a high-level link between the base station and the specific terminal, and receive information reported by the terminal on the high-layer link, such as reference signal receiving power (Reference Signal Receiving Power, RSRP) and Reference Signal Receiving Quality (RSRQ), and when the high-layer link establishment or reconfiguration is triggered, acquiring and analyzing the existing information stored in the base unit stored in the storage unit 523 The high layer signaling information for the specific UE is generated, and the process of the physical layer is semi-statically configured.

The process of receiving the RSRP and RSRQ reporting information is performed by the base station, and the base station extracts the data stream sent by the terminal on the upper layer link by using the high layer signaling receiving signal 522, and then the RSRP/RSRQ measurement report included in the high layer information processing unit 520. The processing unit 521 extracts RSRP/RSRQ information in the data stream, and obtains an RSRP or RSRQ value measured by the terminal for each cell. The process of generating the high-level signaling information refers to that the base station passes the high-layer signaling configuration unit.

The CSI feedback object and the CQI table configuration unit 518 included in 517 perform CQI mapping table configuration for a specific CSI feedback object of a specific terminal. When the high-level link establishment or reconfiguration of the base station and the specific UE is triggered, the CSI feedback object and the CQI table configuration unit 518 generate high-level signaling information by using the existing information of the base station, and generate a channel state for the specific CSI feedback object of the specific terminal. The CQI mapping table used in the information is specified, and the result specified by the CQI mapping table is stored in the high-level configuration information storage table 527 which will be described later. The high-level signaling includes configuration information related to the CQI mapping table. When configuring multiple CSI feedback objects, the CQI mapping table can be configured separately for different CSI feedback objects. The specific high layer signaling format will be described later. The generated high-level signaling sending signal 519 is sent to the target base station through the high-level signaling link, and the high-level signaling sending signal 519 including the high-layer signaling is sent, and the specific CSI feedback object of the terminal can be specified to use the specific CQI mapping table to Get accurate channel quality information for high-order modulation applications.

In addition, the physical layer receiving unit 501 is configured to receive data and signaling sent by the terminal in the cell to the base station through the uplink channel, complete processing of a series of signals, such as radio frequency processing, baseband demodulation, and decoding, to obtain specific uplink data and Signaling information.

The physical layer transmitting unit 516 is configured to map the generated PDSCH, the PDCCH, the reference signal, and the like to the time-frequency resource, and perform baseband-to-radio conversion, and use the multiple antennas of the base station to transmit the downlink signal.

The physical layer receiving unit 501 and the physical layer transmitting unit 516, as a module for transmitting and receiving data of the base station at the physical layer, can be implemented by referring to the relevant modules in the conventional base station and applying the input and output hardware in the existing base station. Therefore, a detailed description is omitted here.

The information collecting unit 502 is configured to collect necessary information required by the base station for configuration or resource allocation of the downlink UE. The information collecting unit 502 includes: a physical layer information feedback processing unit 503, based on the information in the high-level configuration information storage table 527 stored in the storage unit 523 of the base station, distinguishing and processing different UEs in the cell based on different CSI feedback objects. The ACK/NACK collecting unit 504 collects ACK/NACK information reported by different UEs in the cell, and stores the information in the HARQ information storage table of the storage unit 523; performs basic CQI mapping unit on the CQI to SINR mapping based on the basic CQI mapping table. 505, in a specific CSI feedback object When the set CQI mapping table is the basic CQI mapping table, the CQI is mapped to the SINR value and stored in the SINR information storage table 525 of the storage unit 523; and the extended CQI mapping unit 506 performs CQI to SINR mapping based on the extended CQI mapping table, When the CQI mapping table configured by the specific CSI feedback object is a CQI mapping table (extended CQI mapping table) including the high-order modulation scheme, the CQI is mapped to the SINR value and stored in the SINR information storage table 525 of the storage unit 523.

The storage unit 523 is configured to store related information of the base station at the physical layer and the upper layer. The storage unit 523 stores: an RRM measurement result storage table 524, configured to store radio resource management (RRM) measurement results of each active terminal in the cell, and is updated based on the output of the high-level information processing unit 520. The SINR information storage table 525 is configured to store a signal to interference and noise ratio (SINR) of the base station-terminal link of each active terminal in the cell, and is updated based on the outputs of the basic CQI mapping unit 505 and the extended CQI mapping unit 506; The information storage table 526 is configured to store all the interrupted HARQ information in the network, and is updated based on the output of the ACK/NACK collecting unit 504. The high-level configuration information storage table 527 is configured to record the base station to each terminal through the high-layer link. Transmitting the high layer signaling information, and updating the specified result of the CQI mapping table configuration of the CSI feedback object of the terminal based on the CSI feedback object and the CQI table configuration unit 518 included in the high layer signaling configuration unit 517; and the CQI history storage table 529 For storing CSI feedback objects of each active terminal in the cell The CQI historical information. The contents of each information storage table in the storage unit will be described in detail later with reference to Figs. 6 to 8 and Fig. 12.

The scheduling unit 507 is configured to determine a corresponding CSI feedback object, allocate an actual channel resource, and select a modulation and coding scheme based on a signal source and an interference state of the terminal device in the scheduling target subframe. The scheduling unit 507 includes an MCS/TBS mapping unit 508 and a resource allocation decision unit 509. The resource allocation decision unit 509 first determines a user who can obtain downlink time-frequency resources at a certain downlink transmission time, and allocates corresponding downlink resources for each user who obtains the transmission opportunity. The MCS/TBS mapping unit 508 then determines the MCS used for downlink transmission and the corresponding Transport Block Size (TSS) based on the SINR values stored in the resource allocation decision and SINR information storage table 525.

The PDCCH generating unit 510 is configured to generate downlink signaling and generate a corresponding downlink signal. The PDCCH generating unit 510 includes a downlink signaling generating unit 511 according to the scheduling unit 507. The resource scheduling decision and the MCS/TBS decision generate downlink control information for a specific terminal. The downlink control information is coded and modulated to generate a downlink signal, and the target terminal is instructed to perform a corresponding receiving behavior.

The PDSCH generating unit 512 is configured to generate a downlink data signal and a reference signal. The PDSCH generating unit 512 includes: a data signal generating unit 513, based on the MCS/TBS decision of the scheduling unit 507, generating a transport block for each scheduled user and generating a downlink data signal through code modulation and subsequent processing; a reference signal The generating unit 514 is configured to generate a downlink reference signal, such as a CRS, a CSI-RS, and a DM-RS, according to the high-level configuration and the scheduling decision. The downlink transmission signal generating unit 515 is configured to multiplex the data signal and the reference signal of each user to the time-frequency resource. In the grid, a downlink transmission signal is generated.

The CQI mapping table decision unit 528 is used to set an appropriate CQI mapping table for each CSI feedback object of each terminal. The CQI mapping table decision unit 528 performs the CQI mapping table decision method for the target CSI feedback object by using the feedback information obtained by the information collecting unit 502. When the specified condition is met, the high-level reconfiguration process of the target CSI feedback object is triggered, the basic CQI mapping table is switched to the extended CQI mapping table, or the extended CQI mapping table is switched to the basic CQI mapping table. Examples of the CQI mapping table decision method are shown in Figs. 10 and 11.

In the base station configuration in FIG. 5, the higher layer signaling configuration unit 517, the higher layer information processing unit 520, and the CQI mapping table decision unit 528 correspond to the "high layer link unit", generate a high layer signaling signal and transmit it to the terminal. And the high-level link unit specifies, according to the channel state information received by the receiving unit, whether the CQI table used by the terminal device is a basic CQI mapping table or an extended CQI mapping table, where the basic The CQI mapping table specifies a correspondence between the CQI index and a modulation mode and a code rate, and the extended CQI mapping table specifies a correspondence between the CQI index and an extended modulation mode and a code rate, and the extended modulation The method includes a modulation mode in the basic CQI mapping table and a high-order modulation mode in which a modulation order is higher than a modulation mode in a basic CQI mapping table; the physical layer receiving unit 501 corresponds to a “receiving unit”, and receives the The channel state information of the terminal device including the CQI index indicating the channel quality; the information collecting unit 502 corresponds to the "information collecting unit", according to the basic CQI mapping table or the extended CQI mapping table for the terminal device specified by the higher layer link unit Mapping the CQI index to the signal to interference and noise ratio information; the scheduling unit 507 corresponds to the "scheduling unit", the root And according to the signal to interference and noise ratio information mapped by the information collecting unit, performing channel resource allocation on the terminal device and selecting a modulation and coding scheme; the physical layer sending unit 516 and the PDCCH generating unit The 510 and PDSCH generating unit 512 corresponds to the "transmission unit", generates a downlink transmission signal according to the resource allocation result of the scheduling unit and the modulation and coding scheme selection result, and transmits to the terminal device.

The format of the table stored in the storage unit 523 will be described below.

Fig. 6 is a view showing an example of the RRM measurement result storage table 524 on the base station side in the present invention. As shown in FIG. 6, the RRM measurement result storage table 524 is used to record the RRM measurement results of each terminal in the current cell. Specifically, the data field includes: a terminal ID 601, which records an ID of a terminal currently associated with the cell; a cell ID 602, records an ID of a cell to which the RRM measurement result reported by each terminal is directed; an RSRP measurement result 603, records The RSRP measurement result reported by each terminal for its corresponding cell ID; the RSRQ measurement result 604 records the RSRQ measurement result reported by each terminal for its corresponding cell ID.

Fig. 7 is a view showing an example of the SINR information storage table 525 in the present invention. As shown in Fig. 7, the SINR information storage table 525 is used to record the base station-terminal link channel quality information of the active terminal in the current cell. Specifically, the data field item includes: a terminal ID 701, which records an ID of a terminal currently associated with the cell; a CSI feedback object ID 702, records an ID of a CSI feedback object configured by each terminal; SINR measurement result 703, record The specific value of the SINR measurement result 703 may be updated according to the mapping result of the basic CQI mapping unit 505 or the extended CQI mapping unit 506 for the SINR measurement result reported by the CSI feedback object.

Fig. 8 is a diagram showing an example of the HARQ information storage table 526 in the present invention. As shown in FIG. 8, the HARQ information storage table 526 is used to record HARQ process information of active terminals in the current cell. Specifically, the data field item includes: a terminal ID 801, which records an ID of a terminal currently associated with the cell; a HARQ process number 802, which records an ID number of each HARQ process of each terminal. The example is FDD LTE, so the maximum number of HARQ processes that each terminal can support is 8; Redundant Version (RV) 803, which records the redundancy version number of the data bits transmitted by the specific HARQ, which is convenient for the system to increase. Redundant HARQ retransmission; MCS message 804, which records the MCS used by the particular HARQ process during the last transmission.

FIG. 9 is a diagram showing an example of CSI feedback related configuration information of the high-level configuration information storage table 527 in the present invention. The high-level configuration information storage table 527 is configured to record specific high-level configuration information of all terminals in the current cell that have established an RRC connection. As shown in FIG. 9, the data domain item related to the present invention includes: a terminal ID 901, which records an ID of a terminal currently associated with the cell; CSI The feedback object ID 902 records the ID of the CSI feedback object configured by each terminal; the CSI-RS resource ID 903 records the CSI-RS resource target of the specific CSI feedback object link; the CSI-IM resource ID 904 records the specific CSI feedback object Linked CSI-IM resource target; CQI mapping table information tag 905, representing a CQI mapping table used by a particular CSI feedback object in generating CSI feedback information. In this example, the CQI mapping table information is marked as 1 meaning that the basic CQI mapping table shown in FIG. 2 is used, and the CQI mapping table information is marked as 2, which means that the extended CQI mapping table shown in FIG. 4 is used. The high-order modulation configuration flag 906 is used to record whether the transmission function based on the high-order modulation is turned on for the terminal. Only when the data field is true, the base station performs the configuration of the extended CQI mapping table for the corresponding terminal and the downlink transmission of the high-order modulation based on the extended CQI mapping table. The setting of the high-order modulation configuration flag of the terminal by the base station may be implemented in various manners, for example, according to whether the terminal has a hardware capability such as a demodulation chip supporting high-order modulation (for example, 256QAM), and has a high-order modulation support. Set this flag to true in the case of hardware capabilities, otherwise set to false.

In this example, for the terminal 1 (the terminal ID 901 in FIG. 9 is 1), the combination of the CSI-RS resource 1 and the CSI-IM resource 1 to which the CSI feedback object 1 is linked is configured as explained above in connection with FIGS. 3 and 23 ( The CSI-RS resource ID 903 and the CSI-IM resource ID 904 of the entry in which the terminal ID 901 is 1 and the CSI feedback object ID 902 is 1 in FIG. 9 are both 1), and the CSI reported by the g卩CSI feedback object 1 is directed to the signal. The signal and interference condition (scenario) of the interference signal from the micro base station 1 and the micro base station 2, so the CSI feedback object 1 cannot obtain a better SINR value, and configures a basic CQI mapping table (the CQI mapping table information flag in FIG. 9) 905 is 1). And the combination of the CSI-RS resource 1 and the CSI-IM resource 2 to which the CSI feedback object 2 of the terminal 1 is linked (the CSI-RS resource of the entry in which the terminal ID 901 is 1 and the CSI feedback object ID 902 is 2 in FIG. 9) The ID 903 is 1, and the CSI-IM resource ID 904 is 2), that is, the CSI reported by the CSI feedback object 2 is directed to a signal and interference condition (scenario) in which the interference signal from the micro base station 1 and the micro base station 2 does not exist, and thus the CSI The feedback object can obtain a better SINR value, and the SINR value has exceeded the mapping range of the basic CQI mapping table, so the extended CQI mapping table is configured (the CQI mapping table information flag 905 in FIG. 9 is 2). The method and specific procedure for configuring the extended CQI mapping table for the terminal 1 will be described below.

Similarly, the terminal 2 in the example of FIG. 3 is at the center of the serving cell, and the interference strength from other cells is low, so the network only configures one CSI feedback object for it, and because of the channel The quality is good, and the extended CQI mapping table is also configured by the CQI mapping table configuration method (the CQI mapping table information flag 905 of the entry with the terminal ID of 2 and the CSI feedback object ID of 1 in FIG. 9 is 2). The terminal N (not shown in FIG. 3) shown in FIG. 9 is located at the boundary of multiple cells, and the received interference signals are more and stronger, and silence of several interference sources cannot bring significant The performance is improved. Therefore, the configured CSI feedback objects can only use the basic CQI mapping table (the CQI mapping table information flag 905 of the entry with the terminal ID N and the CSI feedback object ID of 1 or 2 in FIG. 9 is 1).

Fig. 12 is a diagram showing an example of a CQI history information storage table 529 in the present invention. As shown in FIG. 12, the CQI history information storage table 529 is used to record the historical CQI reported by each CSI feedback object of the active terminal in the current cell. Specifically, the data field includes: a terminal ID 1201, records an ID of a terminal currently associated with the cell; a CSI feedback object ID 1202, records an ID of a CSI feedback object configured by each terminal; and receives a subframe number 1203, The recording terminal receives the subframe identifier of the CQI reported by the specific CSI feedback object. The CQI measurement result 1204 records the CQI measurement result reported by the CSI feedback object of each terminal for the corresponding subframe. The number of columns in the CQI history information storage table 529 corresponds to the number of times of reporting the history CQI and the window size for judging whether the history CQI is reserved. The history of receiving time earlier than the window range CQI will be eliminated. The number of columns in the CQI history information storage table 529, as indicated by the ellipses in the middle portion, may be increased or decreased depending on the actual situation.

Figure 10 is a flow chart showing the switching of the CQI mapping table from the basic CQI mapping table to the extended CQI mapping table by the higher layer link in the present invention, which is performed by the CQI mapping table decision unit 528 in the base station. To simplify the description, a basic CQI mapping table containing only low-order modulation is defined as CQI_table _N _ ₁ to define an extended CQI mapping table containing higher-order modulation as CQI_table _N . A system supporting transmission using a high-order modulated MCS in the present invention includes a total number of CQI-tables of at least 2 (N is greater than or equal to 2).

The base station will only perform this method for terminals whose high order modulation configuration flag 906 is true. The configuration of the CSI feedback object of the terminal 1 by the base station is taken as an example. Since Fig. 10 shows the flow of switching from the basic CQI mapping table to the extended CQI mapping table, it is assumed that all the CSI feedback objects of the terminal 1 in the initial state use the basic CQI mapping table (CQI_tables).

After receiving the ACK/NACK information from the ACK/NACK collecting unit 504 (step 1001), the CQI mapping table decision unit 528 first determines the corresponding transmission time of the downlink transport block. And the interference status, according to the CSI-RS and CSI-IM linked by all CSI feedback objects recorded in the high-level configuration information storage table 527, find out the signal and interference status (ie, CSI-RS and CSI-IM) Corresponding CSI feedback object (get the corresponding CSI feedback object ID, step 1002). After finding the corresponding CSI feedback object, such as CSI feedback object 3, the decision unit determines whether the downlink transport block is initially transmitted instead of retransmitting based on the HARQ information storage table 526 (the determination may take any achievable method of the prior art, This is not described here again, and based on the high-level configuration information storage table 527, it is judged whether or not the CQI mapping table CQI_table _N-1 (the basic CQI mapping table shown in FIG. 2) currently used by the corresponding CSI feedback object has a next-level CQI mapping table. CQI_table _N (that is, for example, whether the CQI mapping table information flag 905 corresponding to the CSI feedback object in the high-level configuration information storage table 527 shown in FIG. 9 is 1) (step 1003). If the two judgments are not all yes, the decision process ends; determining that the downlink transport block is the initial transmission, and determining that the CQI mapping table CQI_table!^ currently used by the corresponding CSI feedback object has a next-level CQI mapping table CQI_table _N (When the CQI mapping table information flag 905 of the CSI feedback object 3 whose terminal ID is 1 shown in FIG. 9 is 1, indicating that it is possible to switch to the extended CQI mapping table), the decision unit from the CQI history information storage table 529 The CQI value based on the downlink transport block scheduling is read, and it is determined whether it is equal to the CQI maximum value of CQI-tables (such as CQI 15 in FIG. 2) (step 1004). If not, it indicates that the SINR value of the current channel of the terminal does not exceed the mapping range of the basic CQI mapping table, and there is no need to switch to the extended CQI mapping table of the higher modulation mode, so the decision process ends; if so, the decision unit is further based on The HARQ information storage table 526 determines whether the transmission rate of the MCS used in the transmission of the downlink transport block is greater than or equal to the transmission rate corresponding to the CQI maximum value of the CQI-tables (step 1005). If not, it indicates that the transmission of the downlink transport block is not sufficient as the basis for performing the CQI mapping table handover judgment, and the decision process ends; if yes, the reconfiguration process of the base station and the terminal high-level link may be triggered, and the CSI feedback object is 3 Reconfigure the CQI mapping table to CQI_table _N (step 1010).

In the above method, after the determination in step 1005 is YES, the reconfiguration process of the base station and the terminal high-level link may be directly triggered, and the CQI mapping table is reconfigured for the CSI feedback object 3 as CQI_table _N (step 1010), but The instantaneous judgment mechanism is likely to produce a so-called "ping-pong effect", which causes the CQI mapping table to be cut between basic and extended, resulting in waste of resources.

In order to avoid such problems, the method of the present invention can also pass the steps shown in FIG. As shown in 1006-1009, increase the cumulative value S based on constant updates. _Ffset determines whether to trigger the reconfiguration process. gP, in the case where the determination in step 1005 is YES, the decision unit further determines whether the feedback information is NACK or ACK (step 1006), and accumulates the offset value S according to the determination result. _Ffset is updated, and it is judged whether the mapping threshold T _hlgh corresponding to the CQI with the highest transmission rate of the high-order modulation and the lowest transmission rate in the extended CQI mapping table is smaller than the mapping threshold T _w and the update corresponding to the CQI maximum value in the basic CQI mapping table. The accumulated offset value S after. _{The sum} of _ffset , that is, whether to judge whether

If the judgment result is no, the decision process ends; if the judgment result is yes, the reconfiguration process of the base station and the terminal high-level link is triggered, and the extended CQI mapping table is specified for the CSI feedback object of the terminal device.

The cumulative offset value S. _Ffset performs update accumulation by quantizing each downlink transmission effect, indicating the use effect of the currently used CQI mapping table and the necessity and possibility of the next-level CQI mapping table. Specifically, the S. _Ffset can be initialized to _OdB and dynamically updated based on downstream transmissions. In the updating process, if the received information is ACK, that is, the corresponding downlink transport block is successfully received, S is updated. _Ffset = S. _Ffset + Step _up (Step 1007), where Step _up is the aggressive offset when receiving the successful transmission of the information, such as 0.055 dB. If the accepted information is NACK, that is, the corresponding downlink transport block fails to be successfully received, then S is updated. _Ffset = S. _Ffset - Step _down (Step 1008), where Step _{d() wn} is the offset when the information is not successfully transmitted, such as 0.5 dB. The offset value S is accumulated. After _ffset update decision unit determines the use of higher order modulation CQI- table _N CQI transmission while the lowest rate (12 in FIG. 4 CQI) map threshold _T hlgh (such as 21dB), is less than CQI- table _N-1 The mapping threshold of the CQI maximum is T _w (eg, 19 dB) and the cumulative offset value S. _{The sum} of _ffset

1009). If not, the decision process ends; if yes, the reconfiguration process of the base station and the terminal high-level link is triggered, and the CQI mapping table is reconfigured for the CSI feedback object 3 as CQI_table _N (歩

1010). The decision process is now complete (step 1011). The mapping threshold T is a value that reflects a one-to-one mapping rule between the CQI and the SINR value, as known to those skilled in the art, and the value can be freely determined within a certain range when implemented. For example, if the mapping threshold of the CQI value 14 is determined to be 17 dB, a SINR value lower than 17 dB cannot be mapped to CQI 14, and a SINR value higher than 17 dB if it is not simultaneously higher than the mapping threshold of CQI 15 (eg, 19dB), will be mapped to CQI 14.

Further, the above-described heading offset Step _up and Step _{d() wn} are fixed values in the range of 0.04 dB to 0.2 dB and 0.4 dB to ldB, respectively. When you take the value, you should enable the switching of the CQI mapping table. After the steps 1002~1005 are satisfied and reach a reasonable number of times, the above values of 0.055dB and 0.5dB are only examples, and the value of Stepd should be greater than Step _up .

11 is a flowchart showing a process in which a high-level link in the present invention performs a CQI mapping table switching from an extended CQI mapping table to a basic CQI mapping table, that is, a CQI mapping table of a specific CSI feedback object is switched from CQI_table _N to CQI-tables. method. It is performed by the CQI mapping table decision unit 528 in the base station.

The configuration of the CSI feedback object 2 of the terminal 1 by the base station is taken as an example. It is assumed that the CSI feedback object 2 of the terminal 1 in the initial state uses an extended CQI mapping table (CQI_table _N ). After receiving the CQI information from the physical layer feedback information processing unit 503 (step 1101), the CQI mapping table decision unit 528 first determines the CQI mapping table CQI_table used by the CSI feedback object to which it belongs based on the high layer configuration information storage table 527. _N exists on a CQI mapping table CQI_table _{N -1} (i.e., for example, high-level configuration shown in FIG. 9 CQI mapping table information storage table 527 corresponding to the object in the CSI feedback 905 whether the flag is 2, ho step 1102). If not, it indicates that the CSI feedback object does not have a previous CQI mapping table, so naturally, the CQI mapping table cannot be switched to the upper level, and the decision process ends; otherwise, the decision unit reads the downlink transport block scheduling from the CQI history information storage table 529. Time-based CQI value, and determine whether the CQI value is greater than or equal to the minimum CQI of the CQI-table _N using the high-order modulation mode (as shown in Figure 4 using the minimum CQI g卩CQI 12 of 256QAM) (step 1103), and Accumulated offset value K. _Ffset to update. The cumulative offset value K. _ffset updated by accumulating the current quantized CQI mapping table using the results of the way, to assess the need and possibility an upwardly CQI mapping table. Said K. _Ffset can be initialized to _OdB and dynamically updated based on downstream transmissions. In the updating process, if the result of the determination in step 1103 is YES, K is updated. _Ffset = K. _Ffset + R _up (step 1104), where R _up is the _edge offset value when a CQI using high order modulation is received. The value may be determined according to the difference between the reported CQI and the minimum CQI of the CQI-table _N using the high-order modulation mode. For example, when the CQI_table _N is as shown in FIG. 4, the terminal 1 reports the CQI on the CSI feedback object 2. = 14, Bay ij R _up = (14-12)*0.2 = 0.4dB. If the result of the determination in step 1103 is no, K is updated. _Ffset = K. _Ffset -

Rdown (Step 1 105), where R _d . Wn is the offset value when receiving a CQI that is not using high-order modulation. The value may be determined according to the difference between the minimum CQI and the reported CQI in the CQI_table _N using the high-order modulation mode. For example, when the CQI_table _N is as shown in FIG. 4, the terminal 1 reports the CQI on the CSI feedback object 2. 10, shell ij R _d. _Nw = (12-10)*0.1 = 0.2dB. The offset value K is accumulated. _Ffset update After that, the decision unit determines the mapping threshold T3⁄4 of the CQI maximum value (CQI 15 in FIG. 2) in CQI_tables. _w (such as 19dB), whether it is greater than CQI—the mapping threshold TH _hlgh (such as 21dB) and cumulative offset K of CQI with high-order modulation and the lowest transmission rate are used in table _N. _{The sum} of _ffset

1106). If not, the decision process ends; if yes, the reconfiguration process of the base station and the terminal high-level link is triggered, and the CQI mapping table is reconfigured for the CSI feedback object 2 as CQI-tables.

1107). The decision process is now complete (step 1108).

In addition, the above-mentioned advancement offsets R _up and R _d . The value of wn is just an example, and the offsets R _up and R _{d are} advanced. Wn is multiplied by the product of the minimum CQI using the high-order modulation method in the reported CQI and the extended CQI mapping table by the product of the first specified value (0.2 in the example of FIG. 11), and the high-order CQI mapping table is used. The difference between the minimum CQI of the modulation method and the reported CQI is multiplied by the product of the second predetermined value (0.1 in the example of FIG. 11), wherein the first predetermined value and the second predetermined value are respectively 0. Any value within the range of ~1, and the second predetermined value is smaller than the first predetermined value.

The high-level link shown in FIG. 10 performs a CQI mapping table switching from a basic CQI mapping table to an extended CQI mapping table, and the high-level link shown in FIG. 11 performs a CQI mapping table from an extended CQI mapping table to a high-order modulation. The basic CQI mapping table switching method is an example of a method for corresponding configuration of a high-level link. The CQI mapping table configuration unit 528 described in the present invention may also implement corresponding configurations by other methods. For example, in step 1003 of FIG. 10, whether the downlink transport block is initially transmitted and whether the CSI feedback object can use the basic CQI mapping table is determined, but the first determination may be omitted. In addition, the two methods of FIG. 10 and FIG. 11 can be incorporated into the data communication method in the wireless communication system of the present invention, and the data signal is transmitted and received between the base station device and the terminal device based on the modulation and coding scheme determined by the CQI table. The data communication method includes the following steps: receiving, the base station apparatus receiving, by the terminal apparatus, channel state information including a CQI index indicating a channel quality; and a high-layer link, the base station apparatus generating a high-level letter And sending a signal to the terminal device, wherein the base station device further uses, according to the channel state information received by the receiving step, the CQI table used by the terminal device in the high layer signaling signal is a basic CQI mapping table. Or an extended CQI mapping table for specifying a correspondence between the CQI index and a modulation mode and a code rate, where the extended CQI mapping table specifies the CQI cable and extended modulation a correspondence between a mode and a code rate, the extended modulation mode including the base The modulation method in the CQI mapping table and the high-order modulation mode in which the modulation order is higher than the modulation mode in the basic CQI mapping table; in the scheduling step, the basic CQI mapping specified by the base station device according to the high-layer signaling transmission signal a table or an extended CQI mapping table, performing channel resource allocation on the terminal device and selecting a modulation and coding scheme; and transmitting, the base station device generating a downlink transmission signal according to the resource allocation result of the scheduling step and the modulation and coding scheme selection result And transmitting to the terminal device.

Figure 13 is a diagram showing an example of a sequence of complete base station-UE downlink data transmission in the present invention. In Fig. 13, various information exchanges that may occur in information feedback between a base station and a terminal are exemplified as a whole, and the embodiments described in the present invention can be used in the behavior of some of the nodes.

As shown in Figure 13, when the terminal applies for downlink data transmission or the base station pages the terminal and performs downlink data transmission, the two parties first establish a connection of the upper layer link (step 1301).

After the base station makes a decision on the high layer configuration based on the existing information (step 1302), the generated configuration information is sent to the terminal as a high layer signaling through the upper layer link (step 1303). Here, an implementation manner of initializing the CQI mapping table for each CSI feedback object of the terminal may be directly using a basic CQI mapping table that does not include high-order modulation, or may calculate an expected broadband SINR of each CSI feedback object according to RSRP. The value is then configured with the appropriate CQI mapping table. Any specific method that can be realized by those skilled in the art can be used for the specific method of the latter, and will not be specifically described in the present invention.

After receiving the corresponding configuration information through the upper layer link, the terminal performs configuration according to the high layer signaling of the base station (step 1304), such as the configuration of the CSI feedback object, the CQI mapping table corresponding to each CSI feedback object, and the like. The terminal measures the channel based on the completed configuration and generates specific feedback information (step 1305), and reports the feedback information to the base station (step 1306).

So far, the initial high-level link establishment and high-level signaling transmission configuration process is completed. After receiving the feedback information of the terminal based on the high layer signaling, the base station 101 performs a scheduling process such as dynamic MCS decision and time-frequency resource allocation based on the feedback information (step 1307), and generates downlink signaling information corresponding to the scheduled terminal. Instructions (step 1308).

If the terminal is scheduled, the base station transmits a downlink signal to the terminal using the allocated physical layer resources (step 1309). The terminal first receives the downlink signaling information sent to itself, adjusts the data signal receiving device based on the obtained control information, receives the downlink data, and generates HARQ feedback information (step 1310). At the same time, channel measurement and CSI feedback generation functions (steps) 1305) It is possible to perform parallel and generate CSI feedback information. The terminal feeds back all feedback information to the base station (step 1306). This process loops until the end of the data transfer or the high-link link reconfiguration is triggered (step 1311, trigger conditions are shown in Figure 10, Figure 11).

If the high-link link reconfiguration is triggered, the base station side performs high-level reconfiguration and transmits the generated configuration information through the upper layer link (step 1303). After receiving the corresponding reconfiguration information through the upper layer link, the terminal performs configuration according to the new high layer signaling of the base station (step 1304), and performs channel measurement and feedback based on the configuration (step 1305). The terminal then cycles through the previous physical layer process until the downstream data transfer is complete (step 1312). When the downlink data transmission is completed, the base station releases the high-layer link connection (step 1313), and the terminal state becomes an idle state.

In addition, the format of the high layer signaling is not particularly limited as long as the necessary feedback mode information and the configuration information in the feedback mode can be transmitted. Fig. 14 is a diagram showing an example of the format of signaling information transmitted on a high-layer link according to the present invention.

As shown in FIG. 14, the signaling information for the feedback part on the upper layer link is a basic unit of CSI feedback object, and a total of N sets of CSI feedback object configuration information 1401, where N is a CSI feedback object configured by the base station for the terminal. Number. For example, the CSI feedback object 1 configuration information includes: CSI-RS index 1402 and CSI-IM index 1403, respectively, for indicating channel state information reference signals and channel states corresponding to the CSI feedback object. The CQI mapping table configuration information 1404 is used to indicate the CQI mapping table configured by the CSI feedback object, that is, the mapping basis for the terminal to generate the CQI; the codebook configuration 1405, instructing the base station to allow the terminal to calculate the target for the CSI feedback object.隹A of the precoding matrix that can be used in CSI

Pick Π o

Fig. 15 is a diagram showing an example of the flow of downlink data transmission in the present invention. As shown in FIG. 15, the process of a complete downlink data transmission starts from the resource scheduling of the scheduling unit, and forms a downlink signal and transmits it to the terminal through the antenna. The present invention describes the entire process by taking a proportional fair scheduling method as an example. The scheduling unit of the base station first reads the latest SINR value of each CSI feedback object of the terminal having the data transmission request in the current base station from the SINR information storage table 525 (step 1501), and then calculates their corresponding band efficiency and generates a proportional fairness amount. Value (Proportional Fair metric PF metric) (Step 1502). Based on the user priority obtained by the PF metric value and the payload size of each user, the base station determines the terminal to which the downlink transmission is to be scheduled and allocates downlink time-frequency resources to them (step 1503). After generating a resource allocation decision, the base station stores based on SINR information. The signal-to-noise ratio of each terminal in the corresponding scheduled time-frequency resource in the table 525 determines the MCS used when transmitting to the corresponding terminal (step 1504). Then, the base station obtains a corresponding TBS index value by using the MCS-Transport Block Size Index (TBS index) mapping table for each scheduled terminal through the PDSCH generating unit 512 (step 1505), according to the TBS mdex value. And the number of allocated resource blocks obtains a specific TBS value, and generates a specific transport block (step 1506), and generates a downlink data signal through subsequent processing such as encoding, modulation, etc. (step 1507). At the same time, the base station determines the length of the downlink control information (Downlink Control Information, DCI) based on the high-order modulation configuration 906 information of each scheduled terminal, and then generates downlink control information for each scheduled terminal by using the PDCCH generating unit 510. A corresponding signal is generated (step 1508). The format of the downlink control information is as shown in FIG. 18. The base station multiplexes various signals and reference signals of all scheduled terminals to generate a specific downlink signal, and transmits it through the antenna (step 1509).

Fig. 16 is a diagram showing an example of MCS-TBS index mapping in the present invention. The table contains the following data fields: MCS indication 1601, indicating the MCS value used to map the TBS index; modulation order 1602, indicating the number of bits carried by the single modulation symbol corresponding to the modulation mode of the MCS; TBS indication 1603, indicating the TBS of the specific MCS Index mapping results. The row corresponding to MCS 0-31 in the table follows the existing MCS-TBS index mapping table. The row corresponding to MCS 32-39 in the table indicates the newly added MCS using 256QAM modulation and the corresponding newly introduced TBS index _0.

Figure 17 is a diagram showing an example of TBS index-TBS mapping in the present invention. The table contains the following data fields: TBS indication 1701, indicating a given TBS index; resource block number 1702, indicating the total number of resource blocks that may be allocated to a single terminal; TBS value 1703 indicating a resource block corresponding to a specific TBS index and a specific allocation The TBS value at the time of the number.

18 is a diagram showing an example of a format of downlink control information for instructing a terminal to receive a downlink transport block from a base station in the present invention. The data field of the downlink control information is defined by the existing downlink control information format, and includes: a carrier indication 1801, configured to indicate a carrier corresponding to the downlink control information; and a resource allocation indication 1802, configured to indicate when the base station allocates the target terminal The uplink power control command 1803 is used to perform power control on the PUCCH transmission of the terminal; the HARQ process indication 1804 is used to indicate the number of the HARQ process of the scheduled downlink transmission; and the data flow number indication 1805 is used to indicate that the resource is scheduled. The downlink data transmission port number, the specific downlink data flow number, and the like; the downlink transport block specific information 1806, which is used to indicate specific information of the downlink transmission block scheduled by the terminal; The PDSCH data mapping indication 1807 is used to indicate a specific distribution of the PDSCH when the PDSCH is not transmitted on the serving cell, and a CRS signal or a CSI-RS signal used to assist the DMRS-based demodulation when demodulating the data signal. The specific information of the downlink transport block includes specific information of at most two downlink transport blocks. The specific information 1808 of each transport block includes a coded modulation mode indication 1809 for indicating a coded modulation mode used by the terminal for the downlink transport block, and a new data indication 1810 for indicating whether the downlink transport block is new data or retransmitted. The redundancy version indication 1811 is used to indicate a redundancy version of the downlink transport block. The coded modulation mode indication 1809 is a variable length data field whose length is 5 bits when using the existing MCS table, and 6 bits when using the MCS mdex shown in FIG. When the base station generates downlink control information for a specific terminal, if the high-order modulation configuration 906 of the terminal is true, the length of the coded modulation mode indication 1809 is 6 bits; if the high-order modulation configuration 906 of the terminal is false, the coding The modulation mode indication 1809 has a length of 5 bits.

Figure 19 is a block diagram of an internal terminal of the present invention for supporting downlink data transmission using a high order modulation based MCS.

As shown in FIG. 19, a terminal supporting MCS using high-order modulation mainly has: a high-layer link information processing unit 1916, a channel estimation unit 1901, an interference estimation unit 1902, a radio frequency receiving unit 1910, a CSI calculation unit 1903, and a PDCCH receiving unit. 1911, a PDSCH receiving unit 1914, a storage unit 1907, an uplink transmitting unit 1909, and the like.

Specifically, the high-layer link information processing unit 1916 is a module related to high-layer link behavior, configured to establish a high-layer link between the terminal and the serving base station, and receive information 1917 sent by the base station on the high-layer link, such as CSI feedback. The object configuration information and the like, the semi-static configuration of the self-receiving function is performed in accordance with the instruction of the base station, and the corresponding high-level configuration information is stored in the storage unit 1907.

The channel estimation unit 1901 and the interference estimation unit 1902 are respectively configured to measure CSI-RS and CSI-IM configured by the terminal, and obtain signal strength information and interference strength information, which are used for calculation of subsequent CSI.

The CSI calculation unit 1903 is configured to generate feedback information calculated based on a certain CSI feedback object. A terminal may have multiple CSI calculation units for CSI parallel calculation of multiple CSI feedback objects configured by the base station. Only two CSI calculation units are depicted as an example in the figure, but the CSI calculation unit of the present invention may be the same number as the number of CSI feedback objects. The CSI calculation unit determines the CQI used by the corresponding CSI feedback object by the signaling configuration processing unit 1904. The mapping table is configured to send the obtained signal strength information and the interference intensity information to the CSI calculation unit 1905 based on the basic CQI mapping table or the CSI calculation unit 1906 based on the extended CQI mapping table to perform CSI calculation, and generate CSI information to be reported.

The radio frequency receiving unit 1910 receives the radio frequency signal through the antenna and converts it into a baseband signal. The baseband signals are sent to the PDCCH receiving unit 1911 and the PDSCH receiving unit 1914, respectively. The former first performs the operations including blind detection, demodulation and decoding through the baseband processing unit 1912, and obtains specific downlink control signaling, and generates configuration information for downlink data reception by the downlink control signaling processing unit 1913. The PDSCH receiving unit performs subsequent processing, such as descrambling, demodulation, and decoding, on the baseband processing unit 1912 based on the configuration information of the downlink control signaling processing unit 1913, such as the MCS used by the downlink transport block, to obtain specific data. The bits are further processed by the downstream data processing unit 1915.

The storage unit 1907 is configured to store various configuration information, dynamic information, buffer data, and the like in the downlink transmission process. The storage unit 1907 includes a high layer configuration information storage table 1908 for recording high layer configuration information of the base station-terminal link. An example of the partial format associated with the CSI feedback object is shown in Figure 20. Other tables, such as HARQ information storage tables, HARQ data buffers, etc., should also be included in the storage unit, and are not listed here because they are not strongly related to the present invention.

The uplink sending unit 1909 is configured to send an uplink signal, such as CSI feedback information carried by a physical uplink control channel (PUCCH) or uplink data carried by a physical uplink control channel (PUSCH). After the CSI information generated by each CSI feedback object of the terminal is processed by the collision, the uplink transmitting unit forms an uplink signal and sends the uplink signal to the base station.

20 is a diagram showing an example of CSI feedback related configuration information of the terminal-side high-level configuration information storage table in the present invention. The example uses the CSI feedback object configuration of the terminal 1 as an example, and the data field includes: a CSI feedback object ID 2001, indicating the ID of the CSI feedback object configured by the terminal; CSI-RS resource ID 2002, recording the CSI of the specific CSI feedback object link. The RS resource target 2003; the CSI-IM resource ID 2003, records the CSI-IM resource target of the specific CSI feedback object link; the CQI mapping table information flag 2004 records the CQI mapping table used by the specific CSI feedback object when generating the CSI feedback information. Using the basic CQI mapping table shown in FIG. 2 in this example, the flag is 1, and the extended CQI mapping table shown in FIG. 4 is marked as 2; the high-order modulation configuration flag 2005, recording whether the network side is turned on based on the high The transmission function of the order modulation. 21 is a flow chart of a CSI measurement and feedback method on the terminal side in the present invention.

Taking the terminal 1 as an example, in Fig. 21, the terminal 1 first obtains signals in the time domain and the frequency domain through the receiving antenna and the radio frequency and baseband processing (step 2101). Then, the channel estimation unit 1901 of the terminal 1 performs channel state parameter estimation based on the channel measurement reference signal contained therein (step 2102), and generates an actual CSI matrix //. At the same time, through the interference estimation unit 1902, the interference estimation resource included in the time-frequency signal is used for interference estimation (step 2103), and the intensity of the external interference at this moment is obtained.

The terminal sends the CSI matrix H and the interference strength information to the respective CSI calculation units 1903. Taking the CSI calculation unit 1 as an example, the signaling configuration processing unit 1904 in the CSI calculation unit 1 of the terminal 1 reads the CQI mapping table information flag 2004 of the corresponding CSI feedback object stored in the high-level configuration information storage table 1908, and determines the CSI. Whether the feedback object is configured to use the extended CQI mapping table CQI_table _N (step 2104).

If the result of the determination is "Yes", the CSI calculation unit 1903 of the terminal 1 uses the CSI calculation unit 1906 based on the extended CQI mapping table to follow the existing flow, and selects the best RI and PMI based on the codebook (if the CSI of the terminal 1) The feedback object 1 is configured to report the RI and PMI modes, calculate the signal to interference and noise ratio at this time, and quantize to CQI based on the extended CQI mapping table CQI_table _N (FIG. 4) including the high order modulation (step 2105). A detailed description is omitted for existing conventional processes.

If the result of the determination is "NO", the CSI calculation unit 1903 of the terminal 1 uses the CSI calculation unit 1905 based on the basic CQI mapping table to follow the existing flow, and selects the best RI and PMI based on the codebook (if the CSI of the terminal 1) The feedback object 1 is configured to report the RI and PMI modes, calculate the signal to interference and noise ratio at this time, and quantize to CQI based on the basic CQI mapping table CQI-table (as shown in Fig. 2) (step 2106). A detailed description is omitted for existing conventional processes.

The generated CSI information is stored in the storage unit 1907, and is sent to the base station through the uplink channel while waiting for an appropriate feedback timing (step 2107).

Fig. 22 is a view showing an example of the flow of downlink data reception in the present invention. As shown in FIG. 22, the process of receiving a complete downlink data starts from the time when the terminal receives the radio frequency signal through the antenna, and decodes the data information contained in the PDSCH. The terminal first receives the radio frequency signal from the base station device through the radio frequency receiving unit, converts it into a baseband signal, and then sends the radio frequency signal to the PDCCH receiving unit and the PDSCH receiving unit (step 2201). Then the terminal passes the PDCCH receiving unit according to the high order The modulation configuration 2005 determines the length of the downlink control information (step 2202), the length of the downlink control information is variable, and is determined by the length of the coded modulation mode indication 1809 in the information. When the high-order modulation configuration 2005 data field is tme, the length of the coded modulation mode indication 1809 in the downlink control information is 6 bits. When the high-order modulation configuration 2005 data field is false, the length of the coded modulation mode indication 1809 in the downlink control information is 5 bits. And detecting the PDCCH based on the length information until the target downlink control information is successfully received (step 2203). Based on the downlink control information, the terminal obtains the MCS index used by each transport block (step 2204). Then, the terminal obtains the corresponding TBS index value and the modulation mode used by the downlink control signaling processing unit 1913 based on the MCS-Transport Block Size Index (TBS index) mapping table, and then according to the TBS index value and the allocated The number of resource blocks obtains a specific TBS value, and the channel coding rate of the transport block is calculated using the TBS value (step 2205). After obtaining the information, the terminal selects a suitable demodulator and decoder through the PDSCH receiving unit (step 2206), and performs subsequent demodulation and decoding processing on the PDSCH signal, and finally obtains downlink data carried in the PDSCH. 2207).

In other words, the present invention further provides a downlink data receiving apparatus in a terminal apparatus, receiving a data signal from the base station apparatus based on a modulation and coding scheme specified by the base station apparatus, including: a radio frequency receiving unit, receiving the base station apparatus The radio frequency signal is converted into a baseband signal and then sent to the PDCCH receiving unit and the PDSCH receiving unit. The PDCCH receiving unit can use the high-order modulation according to whether the base station device specifies whether the base station device specifies the terminal device or not. a high-order modulation configuration flag of the method, determining a length of downlink control information from the base station device, and performing a PDCCH detection attempt on the baseband signal received by the radio frequency receiving unit based on the determined length of the downlink control information, Until the downlink control information of the target device is successfully received, and the modulation and coding scheme used by the base station device is obtained based on the downlink control information; the PDSCH receiving unit is configured according to the PDCCH receiving unit a modulation coding scheme determining the base station Using a modulation scheme and a channel coding rate, selecting a suitable demodulator and decoder, and performing demodulation, decoding, and the like on the baseband signal received from the radio frequency receiving unit to obtain downlink data from the base station apparatus. .

According to still another aspect of the present invention, a downlink data receiving method in a terminal apparatus, for receiving a data signal from the base station apparatus based on a modulation and coding scheme specified by a base station apparatus, includes the following steps: The receiving unit in the receiving unit receives the base a radio frequency signal of the station device, and converted into a baseband signal and sent to the PDCCH receiving unit and the PDSCH receiving unit; the PDCCH receiving unit, according to the terminal device, indicating whether the base station device specifies the terminal device Determining, by using a high-order modulation configuration flag of the high-order modulation mode, a length of downlink control information from the base station device, and performing, on the basis of the determined length of the downlink control information, a baseband signal received from the radio frequency receiving unit PDCCH detection attempt, until the downlink control information of the target device is successfully received, and obtaining a modulation coding scheme used by the base station apparatus based on the downlink control information; and the PDSCH receiving unit according to the PDCCH The modulation and coding scheme obtained by the receiving unit determines a modulation mode and a channel coding rate used by the base station apparatus, selects a suitable demodulator and decoder, and solves a baseband signal received from the radio frequency receiving unit. Processing, decoding, etc., to obtain downlink data from the base station device Step.

Preferably, in the downlink data receiving apparatus or method, the high-order modulation configuration flag indicates that the base station apparatus specifies that the terminal apparatus can use the high-order modulation mode, and the downlink control information has a length of 6 bits. The high-order modulation configuration flag indicates that when the base station apparatus does not specify that the terminal apparatus can use the high-order modulation scheme, the length of the downlink control information is 5 bits.

Further preferably, in the above-described downlink data receiving apparatus or method, the high-order modulation method is a modulation method in which the modulation order is 256QAM or more.

In the method and apparatus that can support high-order modulation, the new MCS combination introduces extra bits, so both the base station and the terminal side need to add some items in the existing DCI format bit size table, because downlink transmission Whether the MCS used is based on 256QAM will bring new possibilities to the bit size of each defined DCI format. Therefore, the terminal needs to add a step of determining the length of the downlink control information from the base station device (for example, step 2202 in FIG. 22) before receiving the DCI, and the high-order modulation configuration flag defined in the table 906 and the table 2005. The role is to indicate whether each terminal is "usable" high-order modulation. According to the present invention, the downlink data receiving apparatus in the terminal determines the length of the downlink control information based on the high-order modulation configuration flag, and can appropriately receive the downlink control information based on the extended DCI format bit size table, thereby realizing the use of high-order modulation. Downlink transmission.

According to the present invention, since an efficient transmission technique based on high-order modulation is introduced at the physical layer, channel capacity can be more fully utilized to obtain a better data transmission rate. At the same time by setting high level The transmission of the configuration information of the CQI mapping table fed back by the link enables the terminal to respond to changes in channel quality in time, and enhances the coverage of the channel quality by the feedback information, ensuring accurate feedback information and scheduling decisions. Sex. Therefore, the performance of the network can be effectively improved.

Claims

claims

1. A base station device that uses feedback information generated based on a CQI table to determine a modulation and coding scheme and transmit and receive data signals between a wireless communication system and a terminal device, which is characterized in that it includes:

A receiving unit, receiving channel state information including a CQI index indicating channel quality from the terminal device;

The high-level link unit generates a high-level signaling signal and sends it to the terminal device. The high-level link unit uses the high-level signaling signal to transmit the signal to the terminal device according to the channel state information received by the receiving unit. It is specified whether the CQI table is a basic CQI mapping table or an extended CQI mapping table, where the basic CQI mapping table specifies the correspondence between the CQI index, the modulation mode and the code rate, and the extended CQI mapping table specifies the The corresponding relationship between the CQI index and the extended modulation method and the code rate. The extended modulation method includes the modulation method in the basic CQI mapping table and the modulation order higher than the modulation method in the basic CQI mapping table. High-order modulation methods;

The information collection unit maps the CQI index into signal-to-interference-to-noise ratio information according to the basic CQI mapping table or the extended CQI mapping table for the terminal device specified by the high-level link unit; the scheduling unit maps the signal-to-interference-to-noise ratio information according to the information collection unit The signal-to-interference-to-noise ratio information is used to allocate channel resources to the terminal device and select a modulation and coding scheme; and

The sending unit generates a downlink transmission signal and sends it to the terminal device according to the resource allocation result of the scheduling unit and the modulation and coding scheme selection result.

2. The base station device according to claim 1, characterized in that,

The terminal device is configured with at least one CSI feedback object, and the CSI feedback object is a combination of different channel state information reference signal CSI-RS resources and channel state information interference measurement CSI-IM resources of the terminal device in the network environment;

The high-level link unit specifies whether the CQI table used is a basic CQI mapping table or an extended CQI mapping table for each CSI feedback object of the terminal device;

The information collection unit maps the CQI index to signal-to-interference-to-noise ratio information for each CSI feedback object of the terminal device;

The scheduling unit determines the corresponding CSI feedback object based on the signal source and interference status of the terminal device, and maps the corresponding CSI feedback object of the terminal device according to the information collected by the information collection unit. The transmitted signal-to-interference-to-noise ratio information is used to allocate channel resources to the terminal device and select a modulation and coding scheme.

3. The base station device according to claim 2, characterized in that,

When the CSI feedback object of the terminal device currently uses the basic CQI mapping table, the high-level link unit determines whether the CQI value based on the current downlink transport block scheduling is equal to the maximum CQI value in the basic CQI mapping table, and the downlink Whether the transmission rate of the MCS used for transport block transmission is greater than or equal to the transmission rate corresponding to the CQI maximum value of the basic CQI mapping table. If the results of both judgments are yes, then the extension is specified for the CSI feedback object of the terminal device. CQI mapping table.

4. The base station device according to claim 3, characterized in that,

Each of the CQI indexes respectively corresponds to a mapping threshold, which is a value that reflects a one-to-one mapping rule between CQI and SINR values;

If the results of the two judgments are both yes, the high-level link unit further accumulates an offset value S according to whether the ACK/NACK information received by the receiving unit is a NACK or an ACK pair. _ffset is updated, and it is determined whether the mapping threshold T _hlgh corresponding to the CQI that uses high-order modulation and has the lowest transmission rate in the extended CQI mapping table is smaller than the mapping threshold T w corresponding to the maximum CQI value in the basic _CQI mapping table. and the updated accumulated offset value S. The sum of _ffset , if Thigj^T^+Sc^et, then the extended CQI mapping table is specified for the CSI feedback object of the terminal device,

The accumulated offset value S. The initial value of _ffset is 0dB,

If the ACK/NACK information is ACK, the accumulated offset value S. _ffset is updated to Soffset = S _offset + Step _up , where Step _up is the step offset when the received information is successfully transmitted,

If the ACK/NACK information is NACK, the accumulated offset value S. _ffset is updated to Soffset = Soffeet - Step _down , where Step _d()wn is the step offset when the information is not successfully transmitted,

Step _up and Step _d . _wn are fixed values in the range of 0.04dB~0.2dB and 0.4dB~ldB respectively.

5. The base station device according to claim 3, characterized in that,

Before making the two judgments, the high-level link unit first judges whether the current downlink transmission block is the first transmission, and if it is the first transmission, then makes the two judgments.

6. The base station device according to claim 2, characterized in that,

Each of the CQI indexes respectively corresponds to a mapping threshold, and the mapping threshold is a value that reflects a one-to-one mapping rule between CQI and SINR values; When the CSI feedback object of the terminal device currently uses an extended CQI mapping table, the higher layer link unit determines whether the CQI value based on the current downlink transport block scheduling is greater than or equal to the CQI of the high-order modulation method used in the extended CQI mapping table. The minimum value is the accumulated offset value K based on the judgment result. _ffset is updated, and the mapping threshold T¾ corresponding to the maximum CQI value in the basic CQI mapping table is determined. Whether _w is greater than the mapping threshold TH _hlgh and the updated cumulative offset k corresponding to the CQI that uses high-order modulation and has the lowest transmission rate in the extended CQI mapping table. The sum of _ffset , if! ¹ !!^〉! ¹ !!^!^]^^, then the basic CQI mapping table is specified for the CSI feedback object of the terminal device,

The accumulated offset value K. The initial value of _ffset is OdB,

If it is determined that the CQI value based on the current downlink transport block scheduling is greater than or equal to the minimum CQI value of the high-order modulation method used in the extended CQI mapping table, then the accumulated offset value K is used. _ffset is updated to K. _ffset = K _offset + R _up , where R _up is the step offset value when receiving CQI using high-order modulation, multiplied by the difference between the reported CQI and the minimum CQI using high-order modulation in the extended CQI mapping table Determined by the product of the first specified value,

If it is determined that the CQI value based on the current downlink transport block scheduling is less than the minimum CQI value of the high-order modulation method used in the extended CQI mapping table, then the accumulated offset value K is used. _ffset is updated to

where R _d . wn is the step offset value when receiving CQI that does not use high-order modulation. It is determined based on the product of the difference between the minimum CQI using high-order modulation and the reported CQI in the extended CQI mapping table multiplied by the second specified value.

The first specified value and the second specified value are any values greater than 0 and less than 1, and the second specified value is smaller than the first specified value.

7. The base station device according to any one of claims 1 to 6, characterized in that,

The number of CQI indexes in the basic CQI mapping table is the same as the number of CQI indexes in the extended CQI index table.

8. The base station device according to any one of claims 1 to 6, characterized in that,

The modulation modes in the basic CQI mapping table include QPSK, 16QAM, and 64QAM, and the high-order modulation mode is a modulation mode with a modulation order above 256QAM.

9. A data communication method in a wireless communication system. The base station device and the terminal device use feedback information generated based on the CQI table to determine the modulation and coding scheme to send and receive data signals. The data communication method is characterized in that: Includes the following steps: The receiving step is: the base station device receives channel state information including a CQI index indicating channel quality from the terminal device;

In the high-level link step, the base station device generates a high-level signaling transmission signal and sends it to the terminal device, and the base station device also generates a high-level signaling transmission signal in the high-level signaling transmission signal based on the channel state information received in the receiving step. It is specified whether the CQI table used by the terminal device is a basic CQI mapping table or an extended CQI mapping table, where the basic CQI mapping table specifies the correspondence between the CQI index, the modulation mode and the code rate, and the extended CQI The mapping table specifies the corresponding relationship between the CQI index and the extended modulation mode and code rate. The extended modulation mode includes the modulation mode in the basic CQI mapping table and the modulation order is higher than that in the basic CQI mapping table. The high-order modulation method of the modulation method;

Information collection step, the base station device maps the CQI index into signal-to-interference-to-noise ratio information according to the basic CQI mapping table or extended CQI mapping table for the terminal device specified in the high-level link step;

Scheduling step, the base station device allocates channel resources to the terminal device and selects a modulation and coding scheme based on the signal-to-interference-to-noise ratio information mapped in the information collection step; and

In the sending step, the base station device generates a downlink transmission signal and sends it to the terminal device according to the resource allocation result and the modulation and coding scheme selection result of the scheduling step.

10. The data communication method according to claim 9, characterized in that,

In the high-level link step, for each CSI feedback object of the terminal device, specify whether the CQI table used is a basic CQI mapping table or an extended CQI mapping table;

In the information collection step, the CQI index is mapped to signal-to-interference-noise ratio information for each CSI feedback object of the terminal device;

In the scheduling step, the corresponding CSI feedback object is determined based on the signal source and interference status of the terminal device, and the signal-to-interference-to-noise ratio information mapped to the corresponding CSI feedback object of the terminal device according to the information collection step is used for the terminal. The device performs channel resource allocation and selects a modulation and coding scheme.

11. The data communication method according to claim 10, characterized in that, When the CSI feedback object of the terminal device currently uses the basic CQI mapping table, the high-level link step determines whether the CQI value based on the current downlink transport block scheduling is equal to the maximum CQI value in the basic CQI mapping table, and the Whether the transmission rate of the MCS used for downlink transport block transmission is greater than or equal to the transmission rate corresponding to the CQI maximum value of the basic CQI mapping table. If the results of both judgments are yes, then the CSI feedback object for the terminal device is specified. Extended CQI mapping table.

12. The data communication method as claimed in claim 11, characterized in that,

If the results of the two judgments are both yes, the high-level link step further determines whether the ACK/NACK information received in the receiving step is a NACK or an ACK pair cumulative offset value S. _ffset is updated, and it is judged whether the mapping threshold T _hlgh corresponding to the CQI that uses high-order modulation and has the lowest transmission rate in the extended CQI mapping table is smaller than the mapping threshold T w corresponding to the maximum CQI value in the basic _CQI mapping table. and the updated accumulated offset value S. The sum of _ffset , if Thigj^T^+Sc^et, then the extended CQI mapping table is specified for the CSI feedback object of the terminal device,

The accumulated offset value S. The initial value of _ffset is 0dB,

13. The data communication method according to claim 11, characterized in that,

In the high-level link step, before making the two judgments, it is first judged whether the current downlink transmission block is the first transmission, and if it is the first transmission, the two judgments are then made.

14. The data communication method according to claim 9, characterized in that,

When the CSI feedback object of the terminal device currently uses the extended CQI mapping table, the high-level link step determines whether the CQI value based on the current downlink transport block scheduling is greater than It is equal to the minimum CQI value of the high-order modulation method used in the extended CQI mapping table, and the accumulated offset value K is calculated based on the judgment result. _ffset is updated, and the mapping threshold T¾ corresponding to the maximum CQI value in the basic CQI mapping table is determined. Whether _w is greater than the mapping threshold TH _hlgh and the updated cumulative offset k corresponding to the CQI that uses high-order modulation and has the lowest transmission rate in the extended CQI mapping table. The sum of _ffset , if! ¹ !!^〉! ¹ !!^!^]^^, then the basic CQI mapping table is specified for the CSI feedback object of the terminal device,

The accumulated offset value K. The initial value of _ffset is OdB,

15. The data communication method according to any one of claims 9 to 14, characterized in that the number of CQI indexes in the basic CQI mapping table and the number of CQI indexes in the extended CQI index table are the same.

16. The data communication method according to any one of claims 9 to 14, wherein the modulation modes in the basic CQI mapping table include QPSK, 16QAM, and 64QAM, and the high-order modulation mode is a modulation order Modulation methods above 256QAM.